what does an 'X' mean, when it is in in the middle of a numberplate?

[Johnny blaze]

I have seen a few cars with 'X' and 'D' respectively in the middle of their numberplates ie: 123 X 456 or 123 D456.

I have always thought D was for a diplomatic car, but answerbankers I work on a market stall and my 500 quid car was worth more then then L reg Mondeo that I saw this D numberplate on.

Surely diplomats can afford something a little bit more special then a Mondeo.. What is going on? and what does the 'X' mean?

[NORMANTHEDOG]

they are both allocated to embassy cars for their staff cars.

[Grunty]

The first three figures identify the country and the other figures identify the individual vehicle.

There is also a diplomatic series that has three letters and one number, like the ones that some people have to match their initials.

[Johnny blaze]

Thank you NOR and GRUNTS.

I can sleep a bit easier now, however I still not sure why my car is worth like 300 pounds more then their car. I saw a L reg mondeo and a J reg golf sporting these plates outside the australian embassy in Mayfair London.

[Toureman]

D is for cars driven by people who have diplomatic immunity, a lot of these drivers have to buy their own cars and as they might only be in this country for a short time they buy a cheap car!

X is used when the DVLA cannot determine the age of the car due to various reasons, lost registration docs, rebuilt cars, imported cars, and many other reasons.

[Johnny blaze]

Toureman thank you for you considered and very helpfull answer. You have answered both my questions perfectly. thanks.

[HCR2]

UK diplomatic issues comprise three digits identifying the foreign embassy, mission or body, then D (for accredited diplomats) or X (for other personnel), followed by a serial of three digits.

Non-age related plates are 'Q' plates (e.g. kit cars where few original parts are used, some imports or if documentation is lost).